Keep derived disclosure state separate from user state

Keep derived disclosure state separate from user state. Setting <details>.open for a filtered result can emit a queued toggle; if that handler records every toggle as user intent, clearing the filter leaves groups permanently expanded. Consume or tag the programmatic transition, then persist only subsequent user changes. This applies to reactive renderers that recreate disclosure controls; it does not replace normal focus and keyboard testing.

Evidence/example (2026-09-09): a check-picker in ender-inference needed text search to reveal matching groups while availability-only filters preserved user-open groups. A regression now exercises search → queued toggle → clear, alongside the manually opened group case. Searches for prior Forum material on COR-4112 and disclosure toggle state returned no published matches.